Method and composition comprising at least three different average particle volume particulates for low damage gravel packing

ABSTRACT

A gravel packing system, method and slurry. The system comprises a blending device to prepare a slurry comprising a carrier fluid suspending first, second and third particulates, wherein the carrier fluid comprises a brine and less than about 2.4 g/L (20 lb per 1000 gallons) of a viscosifier, and wherein the sum of the mass of the particulates is greater than about 2.4 kg/L (20 pounds per gallon), wherein the first average particle volume is between 27 and 3375 times larger than the second average particle volume, which in turn is between 27 and 3375 times larger than the third average particle volume. The system can also include tubing to position a screen in the wellbore and a slurry pump to circulate the slurry from the blending device in the wellbore in any order such that the particulates are deposited in the screen annulus to form a gravel pack.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Ser. No. 12/124,910, filedMay 21, 2008, now U.S. Pat. No. 7,789,146, which claims priority to U.S.Provisional Application No. 60/951,780 entitled “FORMATION PERMEABILITYCONTROL FLUIDS HAVING OPTIMIZED PACKING VOLUME FRACTION”, filed Jul. 25,2007, now expired, both of which are hereby incorporated herein byreference.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

Gravel packs are placed in wellbores between a screen and a formationface and/or casing to prevent formation sand from flowing into thewellbore and to improve wellbore and near-wellbore conductivity. Theconductivity at the wellbore and near-wellbore is important because anydamage in these locations significantly increases the pressure drop offluid flow, thereby reducing the producibility or injectivity of thewell.

Further, current placement techniques for gravel packs can be a complexprocedure requiring several stages and the proper functioning of movingparts in a hostile wellbore environment. Accordingly, there is a demandfor further improvements in this area of technology.

SUMMARY

Some embodiments are unique procedures for creating a high solidfraction fluid. Other embodiments include unique systems, methods, andapparatus for low damage gravel packing. Further embodiments, forms,objects, features, advantages, aspects, and benefits shall becomeapparent from the below description and drawings.

In some embodiments, a slurry of different amounts and sizes ofparticulates which may formed at least in part of degradable materialare combined with a carrier fluid and placed into a well along with ascreen. The slurry may be first placed in a wellbore and a screenpositioned in the slurry, or vice versa. A reactive solid may be usedreact with at least one of a degradable particulate and/or a hydrolysisproduct of the degradable material. Any of the particulates mayoptionally include a tackifying agent, and/or a coating. Degradablematerials may be formed of any suitable material, including, but notlimited to: a wax; an oil-soluble resin; a material soluble inhydrocarbons; a lactide; a glycolide; an aliphatic polyester; a poly(lactide; a poly (glycolide; a poly (£-caprolactone; a poly(orthoester); a poly (hydroxybutyrate); an aliphatic polycarbonate; apoly (phosphazene); a poly (anhydride); a poly (saccharide); dextran;cellulose; chitin; chitosan; a protein; a poly (amino acid); a poly(ethylene oxide); a copolymer including poly (lactic acid) and poly(glycolic acid); a copolymer including a first moiety which may be ahydroxyl group, a carboxylic acid group, or a hydro carboxylic acidgroup, and a second moiety which is at least one of glycolic acid andlactic acid; or any combination thereof. The reactive solid may be anysuitable material, including, but not limited to, ground quartz, oilsoluble resin, degradable rock salt, clay, zeolite, magnesium hydroxide,magnesium carbonate, magnesium calcium carbonate, calcium carbonate,aluminum hydroxide, calcium oxalate, calcium phosphate, aluminummetaphosphate, sodium zinc potassium polyphosphate glass, sodium calciummagnesium polyphosphate glass, or any combination of these. The carrierfluid used in embodiments may be a brine, water, or any other suitableaqueous or nonaqueous fluid. The sum of the mass of the particulates maybe at least about 2.4 kg per liter of carrier fluid (20 pounds pergallon). The carrier fluid may have a viscosifier present in an amountless than about 2.4 g per liter of carrier fluid (20 lb per 1000gallons), and optionally, the sum of the mass of the particulates is atleast about 2.75 kg/L (23 pounds per gallon), incorporated in aneffective amount, such as, but not limited to, an amount less than 2.15g/L (18 lb gel per 1000 gallons) of carrier fluid, and optionally thesum of the mass of the particulates is at least about 2.75 kg per liter(23 pounds per gallon) of carrier fluid. Any of the above features,taken either alone or in any combination may be used in embodiments.While some embodiments of the invention describe the use of pluralityamounts of particulates, the terms “first amount”, “second amount”,“third amount”, and so on, may be meant in some embodiments to alsodescribe the order of use or addition, while in other embodiments, theterms have no correlation to order of use or addition.

In some aspects a slurry is prepared by combining a carrier fluid, afirst amount of particulates, a second amount of particulates, and athird amount of particulates, the first amount of particulates have afirst average size distribution, the second amount of particulates havea second average size distribution, and the third amount of particulateshave a third average size distribution. The first average sizedistribution is at least three times larger than the second average sizedistribution, and the second average size distribution is at least threetimes larger than the third average size distribution. At least one ofthe second amount of particulates and the third amount of particulatesare formed, at least in part, of degradable material and at least one ofthe second amount of particulates and the third amount of particulatesincludes a reactive solid. A screen is positioned in a wellbore, theslurry circulated through the wellbore such that the first amount ofparticulates, the second amount of particulates, and the third amount ofparticulates are deposited on an outer surface of the screen.

In another aspect, a carrier fluid, a first amount of particulates, anda second amount of particulates are combined into a slurry, where thefirst amount of particulates have a first average size distribution, thesecond amount of particulates have a second average size distribution,and the first average size distribution is at least three times largerthan the second average size distribution. The slurry is placed into awellbore a screen lowered into the slurry. The sum of all particulatesin the slurry may exceed thirty pounds per gallon of carrier fluid insome embodiments. Also, the first average size distribution may bebetween about six and ten times larger than the second average sizedistribution. Further, in some embodiments, the second amount ofparticulates including a degradable material, and the wellbore is shutin for an effective time period. Optionally, particulates may have acoating structured to degrade within the shut in time period. Further,in some instances, at least one of the first amount of particulates andthe second amount of particulates includes a formation face damageremoval agent.

In yet another aspect, systems are provided which include a slurrycomprising a carrier fluid suspending a first amount of particulates, asecond amount of particulates, and a third amount of particulates; thefirst amount of particulates having a first average size distribution,the second amount of particulates having a second average sizedistribution, and the third amount of particulates having a thirdaverage size distribution. The first average size distribution isbetween three times and fifteen times larger than the second averagesize distribution, and the second average size distribution is betweenthree times and fifteen times larger than the third average sizedistribution. At least one of the second amount of particulates and thethird amount of particulates includes a degradable material, and atleast one of the second amount of particulates and the third amount ofparticulates includes a reactive solid. Also included are a screendisposed in a wellbore, and suitable device for depositing the firstamount of particulates, the second amount of particulates, and the thirdamount of particulates between the screen and the wellbore. The carrierfluid may further include a fourth amount of particulates, the fourthamount of with an average size distribution, where the third averagesize distribution between three times and fifteen times larger than thefourth average size distribution. Optionally, the carrier fluid mayfurther suspend a fifth amount of particulates, the fifth amount ofparticulates having a fifth average size distribution, and the fourthaverage size distribution is between three times and fifteen timeslarger than the fifth average size distribution.

In yet another aspect, a system includes a slurry formed of a carrierfluid suspending a first amount of particulates, a second amount ofparticulates, and a third amount of particulates. The carrier fluidincludes a brine and a viscosifier in an amount less than about 2.4 gper liter (20 lb per 1000 gallons) of carrier fluid, and the sum of themass of the particulates is greater than about 2.4 kg per liter (20pounds per gallon) of carrier fluid. The first amount of particulateshas a first average particle volume, the second amount of particulateshas a second average particle volume, and the third amount ofparticulates has a third average particle volume. The first averageparticle volume is between 3³ (27) and 15³ (3375) times larger than thesecond average particle volume, and the second average particle volumeis between 3³ (27) and 15³ (3375) times larger than the third averageparticle volume. The system further includes a screen disposed in awellbore and suitable device for depositing the first, second, and thirdamount of particulates between the screen and a surface of the wellbore.In some embodiments, the first average size distribution is about 840μm, the second average size distribution about 150 μm, and third averageSize about 15 μm. Each median size may have a characteristic dimension.The first, second, and third amount of particulates may have a combineddry packing volume fraction greater than 0.75, or even greater than 0.8.The device for depositing the first, second and third amount ofparticulates between the screen and a surface of the wellbore may alsoinclude the ability for positioning the slurry in the wellbore andpositioning the screen in the slurry.

In some other embodiments, systems are disclosed which include a slurryformed from a carrier fluid suspending a first, second, and third amountof particulates. The first amount of particulates has a first averagesize distribution, the second amount, a second average sizedistribution, and the third amount, a third average size distribution.The first average size distribution is at least three times larger thanthe second average size distribution, and the second average sizedistribution is at least three times larger than the third average sizedistribution. At least one of the second amount of particulates and thethird amount of particulates may include a degradable material, and atleast one of the second amount of particulates and the third amount ofparticulates may include a reactive solid structured to react with atleast one of the degradable material and a hydrolysis product of thedegradable material. The system also includes a screen disposed in awellbore and device for depositing the first, second, and third amountof particulates between the screen and a surface of the wellbore. Thefirst average size distribution may be between about six time and tentimes larger than the second average size distribution. In some cases,at least one of the second amount of particulates and the third amountof particulates include a formation face damage removal agent; and, theformation face damage removal agent may further include an agent toremove at least one damage type selected from gravel pack fluid filtercake, a drilling mud filter cake, a fluid loss agent, and a drilling mudpill residue.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic diagram of a system for low damage gravel packing.

FIG. 2 is a schematic diagram of a device for depositing particulatesbetween an outer surface of a screen and a surface of a wellboreformation.

FIG. 3A is a schematic diagram of a device for depositing particulatesbetween an outer surface of a screen and a surface of a wellboreformation in a first position.

FIG. 3B is a schematic diagram of a device for depositing particulatesbetween an outer surface of a screen and a surface of a wellboreformation in a second position.

FIG. 4A is a schematic diagram of a device for depositing particulatesbetween an outer surface of a screen and a surface of a wellboreformation in a first position.

FIG. 4B is a schematic diagram of a device for depositing particulatesbetween an outer surface of a screen and a surface of a wellboreformation in a second position.

FIG. 4C is a schematic diagram of a device for depositing particulatesbetween an outer surface of a screen and a surface of a wellboreformation in a third position.

FIG. 5 is an illustration of a carrier fluid combined with a first,second, and third amount of particles in a slurry.

FIG. 6 is an illustration of a carrier fluid combined with a first,second, and third amount of particles in a slurry.

FIG. 7 is a schematic flow diagram of operations for low damage gravelpacking.

FIG. 8 is a schematic flow diagram of a technique for low damage gravelpacking.

DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

At the outset, it should be noted that in the development of any suchactual embodiment, numerous implementation-specific decisions must bemade to achieve the developer's specific goals, such as compliance withsystem related and business related constraints, which will vary fromone implementation to another. Moreover, it will be appreciated thatsuch a development effort might be complex and time consuming but wouldnevertheless be a routine undertaking for those of ordinary skill in theart having the benefit of this disclosure. In addition, the compositionused/disclosed herein can also comprise some components other than thosecited. In the summary and this detailed description, each numericalvalue should be read once as modified by the term “about” (unlessalready expressly so modified), and then read again as not so modifiedunless otherwise indicated in context. Also, in the summary and thisdetailed description, it should be understood that a concentration rangelisted or described as being useful, suitable, or the like, is intendedthat any and every concentration within the range, including the endpoints, is to be considered as having been stated. For example, “a rangeof from 1 to 10” is to be read as indicating each and every possiblenumber along the continuum between about 1 and about 10. Thus, even ifspecific data points within the range, or even no data points within therange, are explicitly identified or refer to only a few specific, it isto be understood that inventors appreciate and understand that any andall data points within the range are to be considered to have beenspecified, and that inventors possessed knowledge of the entire rangeand all points within the range.

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended, such alterations and furthermodifications in the illustrated embodiments, and that such furtherapplications of the principles of the invention as illustrated thereinas would normally occur to one skilled in the art to which the inventionrelates are contemplated and protected.

FIG. 1 is a schematic diagram of a system 100 for low damage gravelpacking. In certain embodiments, the system 100 includes a well 102drilled through an overburden 104 and a formation of interest 106. Theformation of interest 106 may include a hydrocarbon producing formation,a water producing formation, a target formation for injection of afluid, or other formation of interest known in the art. In certainembodiments, the well 102 has a wellhead 108, and a casing 110 coveringat least a portion of the wellbore. In the illustration of FIG. 1, thewellbore through the formation of interest 106 is an “open hole”completion in a vertical well. Other types of completions arecontemplated in the present application, including without limitation: acased completion, multiple zone completions, and/or a horizontal well orwell segment. The casing 110 may include a cement layer (not shown)between the casing 110 and the formation(s) (104, 106). Various otherfeatures of the system 100 that are known in the art are not shown ordescribed herein to avoid obscuring aspects of the present application.

The system 100 further includes, in certain embodiments, a screen 112disposed in the wellbore. The screen 112 may include slots or holessized to prevent the flow of particles from the formation of interest106 into the well 102 or to the surface during treatment flowback orproduction of the well 102. In certain embodiments, the system 100includes a gravel pack 114 deposited between the screen 112 and theformation of interest 106. The gravel of the gravel pack 114 may bedeposited as a portion of a slurry 116 comprising particles (118, 120)and a carrier fluid 122.

In certain embodiments, the slurry 116 includes a first amount ofparticulates 118 having a first average size distribution and a secondamount of particulates 120 having a second average size distribution. Incertain embodiments, the first amount of particulates 118 arenon-deformable particulates. The average size distribution is determinedaccording to any method understood in the art, at least including a meshscreen Size number (e.g. 20/40 mesh sand), a mean particle size, and amedian particle size. The average size distributions of the first amountof particulates 118 and the second amount of particulates 120 areselected such that the first average size distribution is between threeand fifteen times larger than the second average size distribution. Theaverage size distributions of the first amount of particulates 118 andthe second amount of particulates 120 are further selected to preventmigration of formation fines through the gravel pack 114 into the well102. In certain embodiments, a larger size distribution (e.g. the firstsize distribution to the second size distribution, or the second sizedistribution to a third size distribution) is a value between six andten times larger. Distributions between six and ten times allow maximalpacked volume fraction (PVF) values while providing a gravel pack thatdoes not shrink, or lose pack efficiency, if smaller particle sizes areremoved.

In certain embodiments, the slurry 116 includes a third amount ofparticulates (not shown—see FIGS. 5-6 and referencing text for examples)having a third average size distribution, where the second average sizedistribution is between three and fifteen times larger than the thirdsize distribution. For example, the first average size distribution maybe a median size of about 840 μm (micrometer, m⁻⁶), the second averagesize distribution may be a median size of about 150 μm, and the thirdaverage size distribution may be a median size of about 15 μm.

In certain embodiments, the slurry 116 includes a fourth and/or a fifthamount of particulates (not shown). The fourth amount of particulatesincludes a fourth average size distribution that is between three andfifteen times smaller than the third average size distribution. Thefifth amount of particulates includes a fifth average size distributionthat is between three and fifteen times smaller than the fourth averagesize distribution.

The median size used herein may be any value understood in the art,including for example and without limitation a diameter of roughlyspherical particulates. In certain embodiments, the median size may be acharacteristic dimension, which may be a dimension considered mostdescriptive of the particles for specifying a size distribution range.In certain embodiments, the first amount of particulates have acharacteristic dimension, for example and without limitation a medianparticle diameter, between about 500 μm and 1800 μm. In certainembodiments, the first amount of particulates includes a median particlevolume between about 2*10⁻¹¹ m³ and 6*10⁻¹⁰ m³. Other volume ranges willbe understood by those of skill in the art to be functional according tothe principles described herein, and all relevant values of particlessizes for gravel packing are contemplated herein.

In certain embodiments, each median size is a characteristic dimension,where the ratio of characteristic dimensions between particle sizes(e.g. first amount of particulates compared to second amount ofparticulates) is proportional to a cube root of a ratio of averageparticle volumes between particle sizes. For example, the first amountof particulates may have a characteristic dimension of 1.5*10⁻³ m and anaverage particle volume of 5.63*10⁻¹⁰ m³. The second amount ofparticulates in the example has an average particle volume between about1.7*10⁻¹³ m³ to 2.1*10⁻¹¹ m³, with a characteristic dimension between1.0*10⁻⁴ m and 5.0*10⁻⁴ m which includes the range from one-third toone-fifteenth the characteristic dimension of the first amount ofparticulates.

The characteristic dimension is used herein to more clearly indicatethat the size selection of the particles in the first and second (and/orthird, fourth, and fifth) particulate amounts are independent of theshape of the particles. Therefore, the particle sizes can vary in eachparticle size step by three to fifteen times in any average linearmeasure, and/or by 3³ times to 15³ times (i.e. 27× to 3375×) in anyaverage volumetric measure. The relative sizing of the particulates maymeet either the linear criteria 3× to 15×, the volumetric criteria 3³×and 15³× or both. In certain embodiments, utilizing a narrower range of5× to 10× (characteristic dimension or linear measure) provides greatersettling time improvement and therefore allows higher particulateloadings and/or lower carrier fluid 122 viscosities.

The carrier fluid 122 may be a brine, a fluid including a hydratable gel(e.g. a guar, other polysaccharide, hydroxyethyl-cellulose “REC”, orother gelling agent), an oil or oilbased gel, a viscoelastic surfactant,a fluid with a viscosifier, a foamed or “energized” fluid (e.g. anitrogen or CO2 based foam), an emulsion (including water or oil in theexternal phase), or other fluid known in the art. In certainembodiments, the slurry 116 is pumped through the well 102 to depositthe first amount of particulates 118 and the second amount ofparticulates 120 between the screen 112 and the formation of interest106. The slurry 116 may be pumped outside the screen 112 into theformation of interest 106 until a screen-out occurs (i.e. theparticulates 118, 120 build up to the point where the pressure dropacross the gravel pack 114 prevents further pumping), the slurry 116 maybe circulated through the well 102 such that the slurry 116 passes fromoutside the screen 112 to inside the screen 112, thereby depositing theparticulates 118, 120 between the screen 112 and the formation ofinterest 106 and circulating the carrier fluid 122 to the surface. Incertain embodiments, the slurry 116 may be placed in the wellbore 102and the screen 112 lowered into the already-placed slurry 116 such thatthe particulates 118, 120 in the slurry 116 are thereby depositedbetween the screen 112 and the formation of interest 106.

In certain embodiments, the mixing of particulates 118, 120 with sizeratios as described herein allow high particulate loadings with a low orzero viscosifier loading. In certain embodiments, the carrier fluid 122includes a brine with no viscosifiers, and the sum of the mass of theparticulates (i.e. the first amount, second amount, and/or third amountcombined) is at least about 20 pounds per gallon of carrier fluid 122.In certain embodiments, the carrier fluid includes a hydratable gellingagent present in an amount less than about 2.4 g gel per liter ofcarrier fluid (20 lb gel per 1000 gallons), for example less than 2.15g/L (18 lb gel per 1000 gallons of carrier fluid), and the sum of themass of the particulates exceeds about 2.75 kg/L (23 pounds per gallon)of carrier fluid 122. In certain embodiments, the carrier fluid 122includes a viscosifier present in an amount less than 2.4 g gel perliter (20 lb gel per 1000 gallons) of carrier fluid 122, and the sum ofthe mass of the particulates exceeds about 3.6 kg/L (30 pounds pergallon) of carrier fluid 122. In certain embodiments, the carrier fluid122 includes a viscosifier present in an amount less than 2.4 g/L (20 lbgel per 1000 gallons), and the sum of the mass of the particulatesexceeds about 3.6 kg/L (30 pounds per gallon) of carrier fluid 122.

The limits for minimum viscosifier loading and maximum particulateloading depend upon factors specific to each system 100 that willordinarily be understood or controlled by those of skill in the art. Forexample, the settling time of the particulates 118, 120 in the carrierfluid 122, the viscosity of the carrier fluid 122, the intended pumpingrate of the slurry 116, the length of the screen 112 interval whereinthe gravel pack 114 is to be placed, the fracture strength of theformation of interest 106, and other factors known to those of skill inthe art all contribute to the viscosifier loading required in aparticular application. Using only brine as a carrier fluid 122 with thelayered particulate sizes 118,120, including a third particulate size,slurries 116 have been developed with particulates exceeding 2.4 kg/L(20 lb per gallon) of carrier fluid 122, and in certain applications theparticulates can exceed 3.6 kg/L (30 lb per gallon) of carrier fluid122.

In certain embodiments, at least one of the smaller particulate sizes(i.e. the second, third, fourth, and/or fifth amount of particulates)include a degradable material. The inclusion of degradable materialallows the particulates to participate in improving suspension ofparticles in the slurry 116, while allowing the particles to be removedin the gravel pack 114 after placement, and/or to allow the particles torelease beneficial chemicals into the gravel pack 114 after placement.For example, the degradation of the particulates may release chemicalsthat dissolve bridging agents, break crosslinked or polymer-basedcarrier fluid 122, and/or that attack a filter cake formed.

Examples of degradable materials include, without limitation, wax,oil-soluble resin, materials soluble in hydrocarbons, lactide,glycolide, aliphatic polyester, poly (lactide), poly (glycolide), poly(£-caprolactone), poly (orthoester), poly (hydroxybutyrate), aliphaticpolycarbonate, poly (phosphazene), poly anhydride), poly (saccharide),dextran, cellulose, chitin, chitosan, protein, poly (amino acid), poly(ethylene oxide), and copolymers including poly (lactic acids) and poly(glycolic acids). In certain embodiments, degradable materials mayinclude a copolymer including a first moiety that is a hydroxyl group, acarboxylic acid group, and/or a hydrocarboxylic acid group, and a secondmoiety that is a glycolic acid and/or a lactic acid.

In certain further embodiments, at least one of the smaller particulatesizes include a reactive solid that reacts with a hydrolysis product ofa degradable material. For example, the second amount of particulates120 may be a degradable material and the third amount of particulatesmay be a material that reacts with the hydrolysis product of the secondamount of particulates 120, enhancing the rate of degradation of thesecond amount of particulates 120. In certain embodiments, the reactivesolid includes ground quartz, oil soluble resin, degradable rock salt,clay, and/or zeolite. In certain embodiments, the reactive solidincludes magnesium hydroxide, magnesium carbonate, magnesium calciumcarbonate, calcium carbonate, aluminum hydroxide, calcium oxalate,calcium phosphate, aluminum metaphosphate, sodium zinc potassiumpolyphosphate glass, and/or sodium calcium magnesium polyphosphateglass. The degradable materials and reactive solids that enhancedegradation may be stored on the same particle, such that reactions donot occur at the surface but begin within the fluids at downholeconditions.

In certain embodiments, at least one of the amount of particulates (i.e.first through fifth) includes an encapsulated breaker that reduces theviscosity of the carrier fluid 122 after placement of the gravel pack114 reducing permeability damage of the pack 114. In certainembodiments, the carrier fluid 122 includes an emulsion, and at leastone of the amount of particulates includes a chemical adapted to assistin breaking the emulsion. In certain further embodiments, the chemicaladapted to assist in breaking the emulsion is encapsulated and/orincluded on a coated particle, such that the chemical is not released tobreak the emulsion until after the gravel pack 114 is placed. In certainfurther embodiments, one or more of the amount of particulates comprisescoated particles, such that the particles do not begin to degrade and/orrelease chemicals, breakers, solvents, and/or surfactants until afterthe gravel pack 114 is placed. Any coating on a particle may be adaptedto break down with time, temperature, fluids expected to be encounteredin the wellbore, chemicals or reactive solids included on otherparticles and/or in the carrier fluid 122 that are released under othermechanisms.

In one exemplary embodiment, the carrier fluid 122 comprises anemulsion, the second amount of particulates includes a surfactant thatbreaks the emulsion and the second amount of particulates are coatedwith a material that breaks down in the presence of a chemical in thethird amount of particulates. In the example, the third amount ofparticulates includes a coating that degrades in the presence ofhydrocarbons (e.g. as produced from the formation of interest 106) thatreleases the chemical breaking down the coating on the second amount ofparticulates. Similar configurations of particles, coatings, chemicals,and the like are contemplated in the present application.

In certain embodiments, one or more of the particulates includes aformation face damage removal agent. The formation face may havepermeability damage from the gravel pack fluid filter cake, from a fluidloss agent in the gravel pack, from a drilling mud filter cake, from afluid loss agent in the drilling mud, and/or residual damage from a pill(e.g. a high viscosity pill pumped during drilling to stop fluid loss)pumped during drilling or completion of the wellbore. The damage removalagent may be a chemical (e.g. an acid and/or an oxidizer) structured toremove formation face damage, and/or a physical agent (e.g. particles ofa specific shape, size, or material to break an emulsion). The damageremoval agent may be any damage removal material known in the art, andmay be included in any of the particulates. Further, and withoutlimitation, the damage removal agent may be within a particle thatenters the fluid in the wellbore on dissolution, and/or is embeddedwithin a coated particle.

In certain embodiments, the amount of particulates 118, 120 compriseparticles having an aspect ratio of less than or equal to one. Incertain embodiments, particles with a lower aspect ratio have enhancedsurface area per unit volume and enhance degradation and/or reactionrates for the particles. In certain embodiments, the amount ofparticulates 118, 120 comprise particles having a nano-structure,micro-structure, or mesoporous structure that enhance the surface areaof the particles. The structures of the particles may be fractal ornon-fractal. In certain embodiments, at least one of the particulates118, 120 includes a tackifying agent such as a resin-coating.

In certain embodiments, the system 100 includes various devices tocontrol mixing and pumping the slurry 116. In one exemplary embodiment,the system 100 includes at least one fluid tank 124 which contains thecarrier fluid 122 and/or a base fluid utilized in the creation of thecarrier fluid 122. The exemplary embodiment further includes a gravelcarrier 126 which, in one embodiment, provides the first amount ofparticulates 118 to a blending device 128. The blending device 128prepares the final slurry 116, for example mixing the gravel fluid 122and adding the first amount of particulates 118 from the gravel carrier126, and further adding any additives, the second amount of particulates120 and/or third amount of particulates. In certain embodiments, morethan one particulate amount may be blended and added by the gravelcarrier 126 or other device. The blending device 128 further providesthe slurry 116 to a pumping device 130 that provides pressurized slurry116 to the wellhead 108. Other equipment configurations are understoodin the art and contemplated herein. For example, and without limitation,the system 100 may include a coiled tubing unit (not shown) in place ofone or more pieces of equipment and/or the tubing 132.

FIG. 2 is a schematic diagram of a device for depositing particulates118, 120 in annulus 203 between an outer surface of a screen 112 and asurface of a formation of interest 106. The slurry 116 is pumped througha crossover tool 202 from a tubing 132 to the screen annulus 203. Thecarrier fluid 122 of the slurry 116 recirculates through the screen 112,depositing the particulates 118, 120 and returning to the surfacethrough a tubing-casing annulus 206. Upon completion of placing thegravel pack 114, the crossover tool 202 is closed, replaced with aproduction packer, or subjected to other operations as known in the art.The placement of the gravel pack 114 as shown in FIG. 2 is exemplaryonly.

FIG. 3A is a schematic diagram of a device for depositing particulates118, 120 in annulus 203 between an outer surface of a screen 112 and asurface of a formation of interest 106 in a first position. The screen112 illustrated in FIG. 3A has slots 302 engageable from the surface insome manner. For example the slots 302 may be engageable throughelectronic signals, hydraulic signals, actuated through a wireline,actuated through force communicated through the tubing 132 (e.g.downward force, upward force, and/or rotational force), and/or throughany other operations understood in the art. In the first position asillustrated in FIG. 3A, the slots 302 are open allowing slurry 116 toflow into the screen annulus 203 and thereby deposit particulates 118,120. As shown in FIG. 3A, the slurry 116 carrier fluid 122 flows intothe formation of interest 106, typically at an injecting pressure belowthe fracturing pressure, until the gravel pack 114 is fully placed.

The arrangement illustrated in FIG. 3A is exemplary only. With certaintools and arrangements the carrier fluid 122 may be returned directly tothe surface instead of being injected into the formation of interest106. For example, the slurry 116 may be pumped down the tubing-casingannulus 206, recirculated through the slots 302 to tubing 132 andreturned to the surface. Alternatively, the slurry 116 may be pumpeddown the tubing 132, forced out of the slots 302 into screen annulus 203and the carrier fluid recirculated through the screen 112, crossing overinto the tubing-casing annulus 206 and returning to the surface. Each ofthese arrangements is well understood in the art and is not shown inFIG. 3A to avoid obscuring aspects of the present application.

FIG. 3B is a schematic diagram of a device for depositing particulates118, 120 between an outer surface of a screen 112 and a formation ofinterest 106 in a second position. In the second position as illustratedin FIG. 3B, the slots 302 are closed preventing the flow of carrierfluid 122 or slurry 116 through the slots. In the embodiment illustratedin FIG. 3B, formation fluid coming from the formation of interest 106flows through the gravel pack 114, screen annulus 203 and screen 112,preventing sand or unconsolidated particulates from the formation ofinterest 106 from flowing into the wellbore or tubing 132. In theembodiment of FIG. 3B, any particles 118, 120 that may have settledinside the screen 112 may be cleaned out by recirculation (e.g. with acoiled tubing unit) and/or by entrainment within produced fluid from theformation of interest 106.

FIG. 4A is a schematic diagram of a device for depositing particulates118, 120 between an outer surface of a screen 112 and a formation ofinterest 106 in a first position. In the embodiment of FIG. 4A, aspecified amount of slurry 116 is placed in the wellbore. The specifiedamount of slurry 116 depends upon the particulate loading of the slurry,the diameter of the wellbore, the length of the interval to be covered,the displacing volume of the screen 112 (which is lowered into theslurry 116), and similar parameters understood in the art. In certainembodiments, the slurry 116 placed at the bottom of the wellbore has avery high particulate loading, for example in excess of 30 lb ofparticulates 118, 120 per gallon of carrier fluid 122 (3.6 kg/L). Thescreen 112 in the first position includes the screen 112 not loweredinto the slurry 116.

FIG. 4B is a schematic diagram of a device for depositing particulates118, 120 between an outer surface of a screen 112 and a formation ofinterest 106 in a second position. The screen 112 in the second positionincludes the screen 112 lowered into the slurry 116. In certainembodiments, the screen 112 may include centralizers such that thescreen 112 is approximately centered in the wellbore. However, where theslurry 116 is dense from heavy particulate loading, the screen 112 tendsto self-centralize and external centralizers may not be required.

FIG. 4C is a schematic diagram of a device for depositing particulates118, 120 between an outer surface of a screen 112 and a formation ofinterest in a third position. In the third position, the screen 112remains in the slurry 116, and production equipment (for example aproduction packer 402) is placed in the wellbore to prepare the systemfor production. In certain embodiments, the well is shut in for aspecified time period to allow particulates 118, 120 in the slurry 116to settle, to allow degradable particulates to decompose completely orpartially, to allow carrier fluid 122 breakers to act on the carrierfluid 122, and/or to allow particulates with tackifiers to cure (e.g.with resin-coated particulates).

FIG. 5 is an illustration of a carrier fluid 122 combined with a first118, second 120, and third 502 amount of particles in a slurry 116. Theparticulates 118, 120, 502 comprise three size regimes, wherein eachsize regime is three to fifteen times larger than the next smaller sizeregime. The inclusion of varying size particulates 118, 120, 502, with ahigh particulate loading, creates a slurry 116 with greatly reducedsettling times relative to a slurry 116 with a uniform particle size.

Further, the amount of carrier fluid 122 per unit volume of slurry 116can be reduced dramatically. For example, spherical particles with auniform packing arrangement create a packing volume fraction (PVF) ofabout 0.74, or about 74% of the slurry volume (where particles aresuspended rather than dissolved) is particulate matter. Sphericalparticles with a random packing arrangement create a PVF of about 0.64.By contrast, an arrangement with three particulate sizes having averagediameters, in one example, of 840 μm, 150 μm, and 15 μm, respectively,creates a mixture of particles having a PVF of about 0.87. The basedensities of the particles 118, 120, 502 may be selected to create afinal slurry 116 density at a selected value. An increase in PVF reducesthe amount of carrier fluid 122 in the final slurry 116. For example, anincrease from 0.64 (random packing) to just 0.80 reduces the amount ofcarrier fluid 122 in a gallon of slurry by nearly 50% (i.e. (36−20)/36).The reduced carrier fluid 122 amount reduces the amount of fluid placedin the formation of interest 106 and the amount of viscosifier (if any)in the gravel pack 114, all contributing to a reduction in permeabilitydamage to the formation of interest 106 and a reduction in permeabilitydamage to the gravel pack 114.

FIG. 6 is an illustration of a carrier fluid 122 combined with a first118, second 120, and third 502 amount of particles in a slurry. In theillustration of FIG. 6, the second amount of particulates 120 includeparticulates having an aspect ratio of less than one. The aspect ratiomay be defined in any direction desired. In the second amount ofparticles 120 illustrated in FIG. 6, the particles are elongated, butmay comprise flakes, disks, ellipsoids, fibers, or any other particulateshapes known in the art. Any of the first amount of particulates 118,second amount of particulates 120, third amount of particulates 502, thefourth amount of particulates (not shown), and/or the fifth amount ofparticulates (not shown) may comprise a non-spherical shape. In certainembodiments, the first amount of particulates 118 comprise the primaryparticulate making up the “gravel,” and the first amount of particulates118 are approximately spherical to maximize permeability of the gravelpack 114.

The schematic flow diagram and related description which followsprovides an illustrative embodiment of performing operations for lowdamage gravel packing. Operations illustrated are understood to beexemplary only, and operations may be combined or divided, and added orremoved, as well as re-ordered in whole or part, unless statedexplicitly to the contrary herein.

FIG. 7 is a schematic flow diagram of a procedure 700 for low damagegravel packing. The procedure 700 includes an operation 702 to combine acarrier fluid, a first amount of particulates, and a second amount ofparticulates into a slurry, where the first amount of particulates havea first average size distribution and the second amount of particulateshave a second average size distribution, where the first average sizedistribution is at least five times larger than the second average sizedistribution, and where the first amount of particulates comprisenon-deformable particulates. In certain further embodiments, theprocedure 700 includes an operation 704 to combine a third amount ofparticulates with the slurry, where the third amount of particulateshave a third average size distribution, and where the second averagesize distribution is at least five times larger than the third averagesize distribution.

The method 700 further includes an operation 706 to position a screen ina wellbore, and an operation 708 to circulate slurry through thewellbore such that the first amount of particulates and the secondamount of particulates are deposited on an outer surface of the screen.In certain embodiments, circulating the slurry through the wellborecomprises flowing the slurry into a formation of interest, and flowingthe slurry back out of the formation of interest such that particulatesfrom the slurry are deposited on the outer surface of the screen.

FIG. 8 is a schematic flow diagram of a technique 800 for low damagegravel packing. The technique 800 includes an operation 802 to combine acarrier fluid, a first amount of particulates, a second amount ofparticulates, and/or a third amount of particulates into a slurry. Thefirst amount of particulates have a first average size distribution, thesecond amount of particulates have a second average size distribution,and the third amount of particulates have a third average sizedistribution. The first average size distribution is at least threetimes larger than the second average size distribution, and the firstamount of particulates comprise non-deformable particulates. The secondaverage size distribution is at least three times larger than the thirdaverage size distribution. The technique 800 in one embodiment furtherincludes an operation 804 to position a screen in a wellbore, and anoperation 806 to deposit each of the amounts of particulates between anouter surface of the screen and a surface of the wellbore, and inanother embodiment, includes operations 808 to position an amount ofslurry on the wellbore, and operations 810 to position the screen in theamount of slurry. In certain embodiments, the technique 800 includesoperations 812 to set a production packer and operations 814 to displacea slurry remainder inside the screen.

In certain embodiments, the simplified operations (relative to currentlyavailable gravel packing operations) of placing the slurry 116 in thewellbore and the screen 112 into the slurry allow a very low carrierfluid 122 viscosifier loading and require a high particulate loading (asin certain embodiments excess carrier fluid 122 is not pumped into theformation of interest 106). In certain embodiments, the carrier fluid122 includes viscosifiers at less than 2.4 g/L (20 lb/1000 gals), andtotal particulate loadings above 3.6 kg/L (30 ppg). In certainembodiments, the slurry 116 includes particulate amounts (for the first,second, third, fourth, and/or fifth amount of particulates) and sizessuch that the packed volume fraction (PVF) for the slurry 116 is greaterthan 0.75 PVF, or in some embodiments greater than 0.8 PVF.

Displacing the slurry remainder inside the screen includes circulatingout particulates inside the screen 112, and/or flowing formation fluidfrom the formation of interest 106 and thereby carrying any slurryremainder out of the screen 112. In certain embodiments, at least one ofthe second and third particulate amounts comprise a degradable material,and the technique 800 further includes an operation 816 to shut in thewellbore for a specified time period. In certain embodiments, thespecified time period may be a time period selected such that variousdegradation and breaking reactions have time to occur before flowingfluids out of the wellbore.

As is evident from the figures and text presented above, a variety ofembodiments are contemplated.

In certain embodiments, a method includes combining a carrier fluid, afirst amount of particulates, and a second amount of particulates into aslurry. The first amount of particulates have a first average sizedistribution and the second amount of particulates have a second averagesize distribution, the first average size distribution is at least threetimes larger than the second average size distribution, and the firstamount of particulates comprise non-deformable particulates. In certainembodiments, the method further includes positioning a screen in awellbore, and circulating the slurry through the wellbore such that thefirst amount of particulates and the second amount of particulates aredeposited on an outer surface of the screen.

In certain further embodiments, the method further includes combining athird amount of particulates with the slurry, wherein the third amountof particulates have a third average size distribution, wherein thesecond average size distribution is at least three times larger than thethird average size distribution. In certain further embodiments, thesecond amount of particulates and the third amount of particulatescomprise a degradable material. In certain further embodiments, at leastone of the first amount of particulates, the second amount ofparticulates, and the third amount of particulates comprise a tackifyingagent. In certain embodiments, the second amount of particulates and/orthe third amount of particulates includes a reactive solid that reactswith a hydrolysis product of the degradable material. In certainembodiments, at least one of the particulate amounts includes particleswith an aspect ratio of less than one.

In certain embodiments, a degradable material includes a wax, anoil-soluble resin, and/or a material soluble in hydrocarbons. In certainembodiments, at least one of the first amount of particulates and thesecond amount of particulates include a reactive solid that reacts witha hydrolysis product of the degradable material. In certain furtherembodiments, the reactive solid includes ground quartz, oil solubleresin, degradable rock salt, clay, and/or zeolite. In certain furtherembodiments, the reactive solid includes magnesium hydroxide, magnesiumcarbonate, magnesium calcium carbonate, calcium carbonate, aluminumhydroxide, calcium oxalate, calcium phosphate, aluminum metaphosphate,sodium zinc potassium polyphosphate glass, and sodium calcium magnesiumpolyphosphate glass.

In certain embodiments, the carrier fluid is a brine, and the sum of themass of the particulates is at least about 20 pounds per gallon ofcarrier fluid. In certain embodiments, the carrier fluid includes aviscosifier being present in an amount less than 2.4 g/L (20 lb per 1000gallons) of carrier fluid, and the sum of the mass of the particulatesis at least about 2.75 kg/L (23 pounds per gallon) of carrier fluid.

In certain embodiments, a method includes combining a carrier fluid, afirst amount of particulates, and a second amount of particulates into aslurry, where the first amount of particulates have a first average sizedistribution and the second amount of particulates have a second averagesize distribution, wherein the first average size distribution is atleast three times larger than the second average size distribution, andwherein the first amount of particulates comprise non-deformableparticulates. In certain embodiments, the method further includespositioning a screen in a wellbore and depositing the first amount ofparticulates and the second amount of particulates between an outersurface of the screen and a surface of the wellbore.

In certain further embodiments, the depositing includes: positioning anamount of the slurry in the wellbore, positioning the screen in theamount of slurry, setting a production packer, and displacing a slurryremainder inside the screen. In certain further embodiments, the screenincludes a crossover sleeve, and the depositing further includespositioning the screen in the wellbore, circulating the slurry throughthe screen from the outer surface to the inner surface of the screenthrough the crossover sleeve, and closing the crossover sleeve. Incertain further embodiments, the second amount of particulates comprisea degradable material, further comprising shutting in the wellbore for aspecified time period.

In certain embodiments, a system includes a slurry including a carrierfluid suspending a first amount of particulates and a second amount ofparticulates. The first amount of particulates have a first average sizedistribution and the second amount of particulates have a second averagesize distribution. The first average size distribution is between threetimes and fifteen times larger than the second average sizedistribution, and the first amount of particulates includenon-deformable particulates. The system further includes a screendisposed in a wellbore, and means for depositing the first amount ofparticulates and the second amount of particulates between the screenand the wellbore.

In certain embodiments, the system further includes the carrier fluidsuspending a third amount of particulates, where the third amount ofparticulates have a third average size distribution, and where thesecond average size distribution is between three times and fifteentimes larger than the third average size distribution. In certainfurther embodiments, the carrier fluid further suspends a fourth amountof particulates, where the fourth amount of particulates have a fourthaverage size distribution, and where the third average size distributionis between three times and fifteen times larger than the fourth averagesize distribution. In certain further embodiments, the system includes acarrier fluid further suspending a fifth amount of particulates, wherethe fifth amount of particulates have a fifth average size distribution,and where the fourth average size distribution is between three timesand fifteen times larger than the fifth average size distribution.

In certain embodiments, the system includes the second amount ofparticulates and/or the third amount of particulates including adegradable material. In certain embodiments, the degradable materialincludes at least one material selected from the list consisting of: alactide, a glycolide, an aliphatic polyester, a poly (lactide), a poly(glycolide), a poly (£-caprolactone), a poly (orthoester), a poly(hydroxybutyrate), an aliphatic polycarbonate, a poly (phosphazene), anda poly (anhydride). In certain embodiments, the degradable materialincludes at least one member selected from the list consisting of: apoly (saccharide), dextran, cellulose, chitin, chitosan, a protein, apoly (amino acid), a poly(ethylene oxide), and a copolymer includingpoly (lactic acid) and poly (glycolic acid). In certain embodiments, thedegradable material includes a copolymer including a first moietycomprising at least one member selected from the functional groupsconsisting of a hydroxyl group, a carboxylic acid group, and ahydrocarboxylic acid group, the copolymer further including a secondmoiety comprising at least one of glycolic acid and lactic acid.

In certain embodiments, the carrier fluid includes a brine, and whereinthe sum of the mass of the particulates is at least about 20 pounds pergallon of carrier fluid. In certain embodiments, the carrier fluidincludes a viscosifier being present in an amount less than 2.4 g/L (20lb per 1000 gallons) of carrier fluid, and wherein the sum of the massof the particulates is at least about 2.75 kg/L (23 pounds per gallon)of carrier fluid. In certain embodiments, the carrier fluid includes ahydratable gelling agent being present in an amount less than 2.15 g/L(18 lb gel per 1000 gallons) of carrier fluid, and wherein the sum ofthe mass of the particulates is at least about 2.75 kg/L (23 pounds pergallon) of carrier fluid.

In certain embodiments, a system includes a slurry including a carrierfluid suspending a first amount of particulates, a second amount ofparticulates, and a third amount of particulates. In certainembodiments, the first amount of particulates has a first averageparticle volume, the second amount of particulates has a second averageparticle volume, and the third amount of particulates has a thirdaverage particle volume. In certain further embodiments, the firstaverage particle volume includes an average particle volume between 27(3³) and 3375 (15³) times larger than the second average particlevolume, and the second average particle volume includes an averageparticle volume between 27 (3³) and 3375 (15³) times larger than thethird average particle volume. In certain embodiments, the systemfurther includes a screen disposed in a wellbore, and a means fordepositing the first amount of particulates, the second amount ofparticulates, and the third amount of particulates between the screenand a surface of the wellbore.

In certain embodiments, the carrier fluid comprises one of a brine and aviscosifier being present in an amount less than 2.4 g/L (20 lb per 1000gallons) of carrier fluid, and the sum of the mass of the particulatesis greater than 2.4 kg/L (20 pounds per gallon) of carrier fluid. Incertain embodiments, the sum of the mass of the particulates is greaterthan 3.6 kg/L (30 pounds per gallon) of carrier fluid.

In certain embodiments, the first average size distribution comprises amedian size of about 840 μm, wherein the second average sizedistribution comprises a median size of about 150 μm, and wherein thethird average size distribution comprises a median size of about 15 μm,wherein each median size comprises a characteristic dimension. Incertain embodiments, the system further includes the first amount ofparticulates, second amount of particulates, and third amount ofparticulates have a combined dry packing volume fraction greater than0.75 or greater than 0.8. In certain embodiments, the means fordepositing the first amount of particulates, the second amount ofparticulates, and the third amount of particulates between the screenand a surface of the wellbore includes means for positioning the slurryin the wellbore, means for positioning the screen in the slurry, andmeans for removing remainder carrier fluid from the slurry.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly some embodiments have been shown and described and that all changesand modifications that come within the spirit of the inventions aredesired to be protected. It should be understood that while the use ofwords such as preferable, preferably, preferred, more preferred orexemplary utilized in the description above indicate that the feature sodescribed may be more desirable or characteristic, nonetheless may notbe necessary and embodiments lacking the same may be contemplated aswithin the scope of the invention, the scope being defined by the claimsthat follow. In reading the claims, it is intended that when words suchas “a,” “an,” “at least one,” or “at least one portion” are used thereis no intention to limit the claim to only one item unless specificallystated to the contrary in the claim. When the language “at least aportion” and/or “a portion” is used the item can include a portionand/or the entire item unless specifically stated to the contrary.

1. A method, comprising: blending a slurry comprising a carrier fluidsuspending a first amount of particulates, a second amount ofparticulates, and a third amount of particulates, wherein the carrierfluid comprises a brine and a viscosifier, wherein the viscosifier ispresent in an amount less than about 20 lb per 1000 gallons of carrierfluid, and wherein the sum of the mass of the particulates is greaterthan about 20 pounds per gallon of carrier fluid; wherein the firstamount of particulates have a first average particle volume, the secondamount of particulates have a second average particle volume, and thethird amount of particulates have a third average particle volume;wherein the first average particle volume comprises an average particlevolume between 27 and 3375 times larger than the second average particlevolume, and wherein the second average particle volume comprises anaverage particle volume larger than the third average particle volume;wherein at least one of the second amount of particulates and the thirdamount of particulates comprise removable particulates; positioning ascreen and circulating the slurry in a wellbore in any order such thatthe first amount of particulates, the second amount of particulates, andthe third amount of particulates are deposited in an annulus between thescreen and a surface of the wellbore; removing the removableparticulates from the annulus to form a gravel pack; producing reservoirfluids through the gravel pack and screen.
 2. The method of claim 1,wherein the sum of the mass of the particulates is greater than about 30lb per 1000 gallons of carrier fluid.
 3. The method of claim 1, whereinthe first amount of particulates, second amount of particulates, andthird amount of particulates have a combined dry packing volume fractiongreater than about 0.75.
 4. The method of claim 1, wherein the slurry iscirculated in the wellbore and then the screen is positioned in theslurry.
 5. The method of claim 1, wherein the screen is positioned inthe wellbore and then the slurry is circulated in the wellbore such thatthe first amount of particulates, the second amount of particulates, andthe third amount of particulates are deposited in the annulus.
 6. Themethod of claim 1, wherein the second average particle volume is between27 and 3375 times larger than the third average particle volume.
 7. Aslurry, comprising: a carrier fluid suspending a first amount ofparticulates, a second amount of particulates, and a third amount ofparticulates, wherein the carrier fluid comprises a brine and aviscosifier, wherein the viscosifier is present in an amount less thanabout 20 lb per 1000 gallons of carrier fluid, and wherein the sum ofthe mass of the particulates is greater than about 20 pounds per gallonof carrier fluid; wherein the first amount of particulates have a firstaverage size distribution and a first average particle volume, thesecond amount of particulates have a second average size distributionand a second average particle volume, and the third amount ofparticulates have a third average size distribution and a third averageparticle volume; wherein the first average particle volume comprises anaverage particle volume between 27 and 3375 times larger than the secondaverage particle volume, and wherein the second average particle volumecomprises an average particle volume larger than the third averageparticle volume, wherein the first amount of particulates, second amountof particulates, and third amount of particulates have a combined drypacking volume fraction greater than about 0.75; and wherein the secondamount of particulates, the third amount of particulates, or acombination thereof comprise particulates removable to form a gravelpack.
 8. The slurry of claim 7, the carrier fluid further suspending afourth amount of particulates, wherein the fourth amount of particulateshave a fourth average size distribution, wherein the third average sizedistribution is larger than the fourth average size distribution.
 9. Theslurry of claim 8, wherein the wherein the third average sizedistribution is between three times and fifteen times larger than thefourth average size distribution.
 10. The slurry of claim 9, the carrierfluid further suspending a fifth amount of particulates, wherein thefifth amount of particulates have a fifth average size distribution,wherein the fourth average size distribution is between three times andfifteen times larger than the fifth average size distribution.
 11. Theslurry of claim 8, the carrier fluid further suspending a fifth amountof particulates, wherein the fifth amount of particulates have a fifthaverage size distribution, wherein the fourth average size distributionis larger than the fifth average size distribution.
 12. The slurry ofclaim 7, wherein the sum of the mass of the particulates is greater thanabout 30 lb per 1000 gallons of carrier fluid.
 13. The slurry of claim7, wherein the second average particle volume is between 27 and 3375times larger than the third average particle volume.
 14. The slurry ofclaim 7, wherein the first average size distribution comprises a mediansize of about 840 μm, wherein the second average size distributioncomprises a median size of about 150 μm, and wherein the third averagesize distribution comprises a median size of about 15 μm, wherein eachmedian size comprises a characteristic dimension.
 15. The slurry ofclaim 7, wherein the first amount of particulates, second amount ofparticulates, and third amount of particulates have a combined drypacking volume fraction greater than about 0.8.
 16. The slurry of claim7, wherein the slurry is stable.
 17. The slurry of claim 7, wherein thesecond amount of particulates comprise particles with an aspect ratio ofless than one.
 18. The slurry of claim 7, wherein the removableparticulates comprise at least one member selected from the groupconsisting of ground quartz, oil soluble resin, degradable rock salt,clay, and zeolite.
 19. The slurry of claim 7, wherein the removableparticulates comprise at least one member selected from the groupconsisting of magnesium hydroxide, magnesium carbonate, magnesiumcalcium carbonate, calcium carbonate, aluminum hydroxide, calciumoxalate, calcium phosphate, aluminum metaphosphate, sodium zincpotassium polyphosphate glass, and sodium calcium magnesiumpolyphosphate glass.
 20. The slurry of claim 7, wherein the removableparticulates comprise at least one member selected from the groupconsisting of: a lactide, a glycolide, an aliphatic polyester, a poly(lactide), a poly (glycolide), a poly (ε-caprolactone), a poly(orthoester), a poly (hydroxybutyrate), an aliphatic polycarbonate, apoly (phosphazene), and a poly (anhydride).
 21. The slurry of claim 7,wherein the removable particulates comprise at least one member selectedfrom the group consisting of: a poly (saccharide), dextran, cellulose,chitin, chitosan, a protein, a poly (amino acid), a poly (ethyleneoxide), and a copolymer including poly (lactic acid) and poly (glycolicacid).
 22. The slurry of claim 7, wherein the removable particulatescomprise a copolymer including a first moiety comprising at least onemember selected from the functional groups consisting of a hydroxylgroup, a carboxylic acid group, and a hydrocarboxylic acid group, thecopolymer further including a second moiety comprising at least one ofglycolic acid and lactic acid.
 23. The slurry of claim 7, wherein theviscosifier comprises a hydratable gelling agent present in the carrierfluid in an amount less than about 18 lb per 1000 gallons of carrierfluid, and wherein the sum of the mass of the particulates is at leastabout 23 pounds per gallon of carrier fluid.